Numerous catalysts have been developed which provide polyolefins with certain advantageous properties. One class of these catalysts are now commonly referred to as metallocenes, organometallic coordination complexes containing one or more .pi.-bonded moieties in association with a metal atom from Groups IIIB to VIII or the Lanthanide series of the Periodic Table of Elements. These catalysts are reportedly highly useful in the preparation of polyolefins because they produce homogeneous polymers at excellent polymerization rates, allowing one to closely tailor the final properties of the polymer as desired.
In U.S. Pat. No. 5,527,752 a novel catalyst precursor was disclosed for use in the manufacture of polyolefins. However, the manufacture of this catalyst on a commercial scale is frustrated by the required employment of cryogenic cooling during the protonation step. This is a complex and costly step to undertake and it makes this class of metallocenes very expensive to manufacture. Accordingly, there existed a need for a simpler procedure for its manufacture.